For example, for a 24 foot wide house with a center floor beam, the total supported length of the floor joist is 24 feet. Then you **divide** this by two to give a supported length of 12 feet. This is the number you will use for supported length.)

## How do you calculate beam size?

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The formula for the section modulus is **beam width times beam depth squared divided by 6**. A two 2-by-6 standard beam has actual dimensions of 1.5-by-5.5 inches which would give a section modulus of 1.5 x 5.5 x 5.5 / 6 = 7.6 which is not enough for this example. A 2-by-8 beam would be sufficient.

**How do you calculate load bearing beam size?**per square foot. Multiply the loading per square foot by the area in square feet of the surface which the beams will be supporting.

**Divide by the number of beams**which will be installed to get the loading per beam.

**How far can a triple 2×10 beam span without support?**

For a more normal-sized deck, the same beam can span 8′, supporting a deck that is 8′ wide. You can also triple a 2×10 beam. In that case, you could span **up to 15′ for decks** that are 4′ wide and up to 10′ for decks that are 8′ wide.

**What size beam do I need for a 24 foot span?**

For 24 foot span, size of simply supported beam for 2-3 storey residential building, using thumb rule, is **about 15″×18″ in** which beam width is 12″ and beam depth is 15″, if width will be kept 12″, depth should increased, then beam size 12″×24″ can be used, providing with 4nos of 16mm bar at top, 4nos of 20mm bar at …

### What size beam will span 20 feet?

To accomplish that, it is common to add a beam to provide that structural support. But getting the right beam size is important. If you are considering a 20-foot span, there is a certain size beam that is required. For 20-foot spans, the wood beam has to be **at least 18 inches in depth**. You may also read, ** How do I calculate heat loss?**

### What size beam do I need to span 15 feet?

For 15 foot span, size of continuous beam for 2-3 storey residential building, using thumb rule, is **about 9″×9″** in which beam width is 9″ and beam depth is 9″ providing with 2nos of 10mm bar at top, 2nos of 12mm bar at bottom and 2nos of 12mm crank bar of Fe500 with stirrup [email protected]″C/C and M20 grade of concrete ratio (1: … Check the answer of ** How do I calculate how much concrete I need for a poured wall?**

### How far can a triple 2×10 beam span?

For a more normal-sized deck, the same beam can span 8′, supporting a deck that is 8′ wide. You can also triple a 2×10 beam. In that case, you could span **up to 15′** for decks that are 4′ wide and up to 10′ for decks that are 8′ wide.

### What size beam can span 12 feet?

Joist Spans | ||
---|---|---|

Species | Size Beam | 12′ |

Southern Pine | 2-2×6 |
4′-7″ |

2-2×8 | 5′-11″ | |

2-2×10 | 7′-1″ |

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### How far can a 4 ply 2×12 beam span?

Look at the table along the row for 12′ of supported length. You will see that a 4-ply, 2 X 12 can span a maximum of **13′** while supporting 12′ joists on either side of it.

### How far can a 2×6 beam span without support?

2-grade 2×6 joists can span up to **10 feet 9 inches** from beam to beam when spaced the standard 16 inches apart with a maximum live load of 30 inches per square foot. In comparison, No. -1 grade lumber can span slightly further to 10 feet 11 inches under the same parameters.

### How big of a beam do I need to span 25 ft?

For 25 foot span, size of simply supported beam for 2-3 storey residential building, using thumb rule, is **about 15″×18″ in** which beam width is 12″ and beam depth is 15″, if width will be kept 12″, depth should increased, then beam size 12″×24″ can be used, providing with 4nos of 16mm bar at top, 4nos of 20mm bar at …

### How far can a beam span without support?

A 2×10 beam – made up of two 2x10s nailed together – can span up to **11′** without support beneath a deck that is 4′ wide. For a more normal-sized deck, the same beam can span 8′, supporting a deck that is 8′ wide.

### How big of a beam do I need to span 30 feet?

If you have a 30-foot span, it is important to know just how long a beam you will need for support. There is a good rule of thumb for this: divide your span (in inches) by 20. So, if your span is 30 feet (or 360 inches) you would divide that by 20 to come **to 18 feet**.

### How long can a Microlam beam span?

If you want your total span between members to be less than 60 feet, you need to measure it. The maximum length of manufactured beams is **sixty feet**.